Tamme-Lauri oak (Estonian: Tamme-Lauri tamm) is the thickest and oldest tree in Estonia, located in Urvaste Parish, Võru County.[1] The height of the tree is 17 metres (56 ft), circumference is 831 centimetres (327 in), measured 130 centimetres (51 in) from the ground.[2] According to researchers, the tree was planted around 1326.[3]
The oak has been hit repeatedly by lighting, damaging the branches, and the center had become empty. During restoration in 1970s an old hideout of forest brothers was found inside the cavity.[4] Seven people could stand inside the tree before it was filled with 8 tonnes (18,000 lb) of reinforced concrete.[5] The tree is still viable, although it has lost its top because of the lightning strikes.[6]
The name of the Tamme-Lauri oak comes from Tamme-Lauri farm, which in turn got its name from the spirit that was thought to live in the oak, bringing bad and sometimes good luck. It was the spirit of fire called Laurits.[5]
Tamme-Lauri oak is depicted on the back side of Estonian ten kroon banknote.[7] The land where the tree is located was bought by Estonian Ministry of the Environment in 2006[6] and the oak has been under protection since 1939.[1]